Cam actuated construction clamp



June 8', 1954 c. J. DODSON ETAL CAM ACTUATED CONSTRUCTION CLAMP FiledOct. 17, 1950 CLARENCE'MGARDNEP @CLAZ/DE JIDODSON ATTORNE'Y PatentedJune 8, 1954 UNITED stares rarsur :oFFICE 2,680,459 CAM ACTUATEDCONSTRUCTION CLAMP Claude J.

Brevard,

.Nemours & Compan vDodson an N. (3., assi d Clarence M. nors to -E. I..y, Wilmington, -Del.,-a 'cor- .poration of Delaware Gardner, du Pont deApplication October 17, 1950,-'-Serial No. 190,599

2 Claims.

setting of the mix.

In the construction of concrete walls, and similarstructures, it hasbeen the practice to employ :relatively large unitarypanel forms, whichmay or in other ways.

b1 ssed by a succession of horizontal timbers, the outer ends of whichare restrained from movement by stakes driven into the ground.

To withstand the severe stresses to which con form elements firmlytogether during erection, so that relative movement between the partscannot occur. For this movement "thatrisrrelia'ble in;

Usually, the assembled forms are finally butof bolt .H.

Another .objectnf :this: invention is to provide a clampfor;the:assembly-:of walessand'stifibacks operation. Another object :oftthis invention is a clamp tofawaiestand :stifibacks which may,

cated I from .astan'dard "stock materials that are usually available,:particularly on construction sites.

Other objects 0 will becom'aaprdetailedxi'escription herein when Fig.1.1's a: toprplan view of one" embodiment of a clamp: made in'accordancewith i this invention,

Fig. 2 .is a side'relevation :viewof thet'clamp 'of Fig. .1,

Fig. 3is-a sectional'view taken along line 3-3 Fig. 41sapersp'ectiveiview showing the manner in which wales LEtIGLSGCIllGdtO:stiffba'cks :by

I this improved icla'mp.

Referring to Figures 1,12 and.3, .oneembodi- 'ment ofclampiaccordingtothis invention com- .prisestwoxelawaarms'iliil which:are provided with holes nearitherearward ends for the reception Nut4.221s :threacledly engaged with provideoluvith a cottertpin (notshown), .to pre- 30 .The central p01- of rollers l3 and claw arms Iii,providing bearing surfaces for rotation of roller I 3 into or out ofclamping position.

Roller I3 is provided The clamp preferably provided with a slidablebearing plate It mounted plate it which is loosely mounted on the armsIt as shown by the horizontal dotted lines in Figure 1 and the verticaldotted lines in Figure 2 will be freely slidable along the arms asroller [3 is rotated into either open or clamping position, while stillbeing prevented from disengagement from the arms. This also permitsfree, vertical claw end of either arm independent of the other duringassembly of the device with the stiiiback and wale.

By reference to Figure 4, it will be seen that when in use the claw armsof the clamp are made to straddle the stifiback 18 with the claw the topwale I9 of the pair of wales. As hereinbefore described, the two walesare secured against the studs of the form panels 20 by wedges 2| andties 22. When handle [5 is depressed to the position shown in Figure 4,roller I3 is turned so that its greater radius is brought to bearagainst plate l6, forcing the plate against the rear surface ofstifiback l8 and thereby locking the stiffback and wales firmlytogether. The clamp may be disengaged by simply pulling handle 15 intoprolongation with claw arms H], which action turns roller I3 so that asmaller radius is interposed between bolt H and plate "5. In the latterposition all tension on arms I0 is released and the claw ends may belifted from the edges of the wales without difficulty.

It will be obvious from the foregoing detailed disclosure of ourinvention that various modifications will suggest themselves to thoseskilled in the art without departing from the spirit thereof, and we donot therefore intend to be limited except as set forth in the followingpatent claims.

We claim:

1. A device for connecting and retaining vertically positionedstifibacks against horizontally positioned wales in temporary forms forconcrete structures and the like, comprising in combination a pair ofindependently adjustable claw arms mounted in parallel spaced relationand capable of assuming a horizontal position when in operation andforming rectangular and unobstructed or free opening therebetween toaccommodate a vertically positioned stifiback while the forward endsengage a wale in horizontal position, a follower comprising a floatingplate member, having openings at its ends loosely engaging each of theclaw arms and serving as the sole supporting means for said follower andlimiting its movement within said free space, means for pivotally andadjustably mounting and maintaining said arms in substantially parallelrelation comprising a bearing means and an elongated eccentricallypositioned cam means rotatably mounted with its end portions engagingthe opposing sides of said claw arms, and means for rotating said cammeans to exert pressure against said floating plate in the direction ofa vertically positioned stifiback when placed within said free space.

2. A device for connecting and retaining vertically positionedstifibacks against horizontally positioned wales in temporary forms forconcrete structures and the like, comprising in combination a pair ofclaw arms mounted in parallel spaced position to accommodate the uprightvertically positioned stifiback therebetween and asflexible oradjustable relationship outside the space or opening provided toaccommodate the stifiback, and pivotally mounted connecting meansmaintaining said arms in said flexible or adjustable position duringassembly comprising a bolt extending through horizontal openings in theend portion of each of the arms, together with a cam means pivotallymounted thereon and serving as the sole means for maintaining said armsin substantially parallel position or relation, and a floating platemember loosely mounted upon each of the arms adjacent to said cam meansand movable by rotating said cam means thereagainst to urge the plate inthe direction of the stiiiback.

a substantially 1 References Cited in the file of this patent UNITEDSTATES PATENTS Number Name Date 60,091 Tice Nov 27, 1866 136,399 WilmotMar. 4, 1873 176,752 Marsh May 2, 1876 256,026 Morden Apr. 4, 1882497,550 Russell May 16, 1893 793,412 Bliss June 27, 19 5 1,084,379 WileJan. 13, 1914 1,273,809 Beazell July 30, l9l8 FOREIGN PATENTS NumberCountry Date 350,791 France Apr. 19, 1905'

